The overall goal of the Imaging Core is to develop, implement, optimize, and validate quantitative surrogate biomarkers of tumor treatment response. This Core will be dedicated to providing scientific and technical resources and support for non-invasive imaging of small animal models of cancer in vivo] and is fundamental to the success of three of the four projects described in this application. Projects supported by the Imaging Core are directed at employing existing as well as novel, targeted therapies which will elicit molecular signatures that can be imaged via optical, SPECT, and PET methods and then complemented with the (downstream) physiological information obtained from ultrasound, MRI, and CT. In particular, Project 1 (PI: Arteaga) and Project 3 (PI: Pietenpol) will employ noninvasive molecular imaging metrics (FLT-PET, FDG-PET, Annexin-V microSPECT and optical) to assess tumor cell proliferation, glucose metabolism, and apoptosis in response to novel therapies. Project 2 (PI: Mundy) will employ noninvasive molecular imaging metrics (bioluminescence, fluorescence, and microSPECT/CT) to track breast cancer metastases to bone and assess bone quality. In addition to providing the methods required by SPORE projects, the Imaging Core will develop techniques that can augment these studies as well as support developmental pilot projects. The equipment and personnel needed to support research by investigators from within the SPORE will be provided by the Center for Small Animal Imaging (CSAI) (see Resources)). Funds obtained through the SPORE will support collaborations with expert imaging science faculty for the development and implementation of cutting edge imaging protocols;support for imaging system operators and technical staff who will handle animal preparation and monitoring as well as operate the instruments;support for data analysis and for quantitative image analysis customized to specific applications, including the coregistration and integration of multiple imaging modalities, histology and proteomics. 1. Provide non-invasive imaging metrics of tumor initiation, progression and treatment response to investigators in the Vanderbilt Breast SPORE. 2. Provide collaborations with expert imaging science faculty for the implementation of cutting edge imaging protocols to address each investigators goals. The Imaging Core will support experts in nuclear, optical, MRI, CT, and ultrasound imaging. 3. Provide support for data analysis and for quantitative image analysis customized to specific applications, including the co-registration and integration of multiple imaging modalities, histology and proteomics.